Klippel-Trénaunay Syndrome

Although Klippel-Trénaunay syndrome is a rare congenital (present at birth) disorder, it is the most common condition involving combined vascular malformations.

The syndrome is characterized by a localized or diffuse capillary malformation (port-wine stain) that overlies a venous malformation and/or lymphatic malformation with associated soft tissue and bone hypertrophy (excessive growth). The port-wine stain (caused by swelling of small blood vessels near the surface of the skin) is typically substantial, varicose veins are often quite numerous, and bone and soft tissue hypertrophy (overgrowth) is variable.

The affected limb is either larger or smaller than the unaffected limb. Hypertrophy occurs most commonly in the lower limbs, but may affect the arms, the face, the head or internal organs. Additionally, a wide range of other skeletal and skin abnormalities may be present (illustration 1). Patients may have an increased extremity circumference and an increase or decrease in the length of the limb.

Bony enlargement is usually not present at birth, but may appear within the first few months or years of life and may become particularly problematic during puberty. The affected area grows longer and thicker due to increased blood supply. Small vesicles (lymphatic blebs) appear within the capillary lesion and can bleed, become irritated and get infected.

In young adults, the capillary malformation may thicken and become more prominent.

Symptoms vary according to the severity of the dominant vascular component and its location. If lymphatic malformations are dominant, soft tissue swelling and enlargement will occur.

If venous malformations are dominant, episodes of painful thrombosis (clotting) and inflammation (phleboliths) will occur. This group of patients often experiences muscle cramping or joint pain when walking.

When the lower gastrointestinal tract (intestines) is involved, rectal bleeding often occurs.

In many patients, a thorough medical history and physical examination are sufficient to make the diagnosis. However, a number of imaging studies are useful when there are complications.

Evaluation of the deep venous system can be done by Doppler ultrasonography (type of ultrasonography in which blood vessels are seen) and magnetic resonance imaging (MRI) studies. MRI is also helpful in imaging the soft tissue hypertrophy. Venography may help evaluate the venous structures.

Patients with Klippel-Trénaunay syndrome can have numerous complications including skin breakdown and ulceration, bleeding and secondary infection.

If the lesion extends deeper in tissue, internal organs such as the sacs that hold the lungs (pleura), spleen, liver, bladder and colon may also be affected. When this happens, internal bleeding or clotting can occur.

Varicosities may affect the superficial and deep venous systems. Pain and lymphedema (swelling of the extremities due to stoppage of lymph flow caused by malformed lymphatic vessels) are common.

Complications due to varicosities include abnormal skin sensations such as burning or tingling (paresthesias), skin ulcers, blood clots in the lung (pulmonary emboli), inflammation and clots of blood vessels in the legs, and skin and soft tissue infection (cellulitis).

Hypertrophy of a limb can lead to vertebral scoliosis, gait abnormalities and compromise of function.

Malformations can be localized in the joint and cause damage secondary to bleeding.

Management of Klippel-Trénaunay syndrome is dependent upon individual symptoms. Although both nonoperative and surgical approaches are used, treatment is primarily nonoperative and supportive. Careful clinical and radiologic assessment of the affected limb should be done at regular intervals to assess for limb-length discrepancy and to formulate an approach for prevention and treatment of overgrowth. For lower-limb overgrowth beyond a 2-centimeter (a bit less than 1 inch) differential, orthopaedic intervention may be necessary.

Supportive Care

Compression therapy. Compression garments are often advised for chronic venous insufficiency, lymphedema, recurrent cellulitis and recurrent bleeding from the capillary or venous malformation. They help to control swelling and pain in the limb and help protect the limb from trauma. Intermittent pneumatic compression pumps and manual lymphatic massages may also provide benefit.

Pain medication, antibiotics, and limb elevation. These treatments are all used to manage cellulitis.

Anticoagulant therapy (the use of substances that prevent blood clotting). This approach is indicated in cases of acute thrombosis (clotting) and is also used as a preventive measure prior to surgical procedures.

Shoe inserts. These are sometimes used to manage limb-length discrepancies that are less than 1 inch. For greater discrepancies, orthopaedic surgery may be considered.

Surgical Interventions

Laser therapy. The flashlamp pulsed-dye laser is often effective in lightening the color of the port-wine stain in a patient with Klippel-Trénaunay syndrome. Many treatments are typically required to achieve a desirable result. Laser treatment is also indicated when there is ulceration and breakdown of lymphatic blebs, since it may speed the healing.

Surgery. Depending on individual circumstances and anatomical involvement a number of surgical options are occasionally advised. These include vein ligation, vein resection, and in rare cases, removal of a problematic area of abnormal tissue (debulking surgery) and amputation. Vein ligation is a procedure that clamps off a section of veins. The clamp prevents blood flow through the damaged section of veins and promotes blood flow through the veins that are not damaged.

Other Treatment

Sclerotherapy. This treatment consists of the injection of a chemical into the vein causing inflammation. As the inner wall of the vein becomes inflamed, blood cannot flow through it. The vein then collapses and forms scar tissue. Sclerotherapy can also be used to damage lymphatic channels.

Low molecular weight heparin (LMWH). This blood thinner (anticoagulant) can improve pain, phleboliths, and improve the risk of bleeding and clotting prior to the procedure.

Rapamycin. Rapamycin has been shown to improve young and old patients’ quality of life by improving pain, softening the malformation and decreasing bleeding from lymphatic blebs.